1. Field of the Invention
The present invention relates to a paper box for packing detergent of powder or particles, and more particularly to an improved packing paper box in which a strip-shaped inlet is attached to an inner surface of the box so that the inlet closes a tear tape portion cut off when the box is opened and which is designed to reduce manufacturing cost, improve productivity and maintain watertightness.
2. Description of the Prior Art
Generally, an usual paper box which is adapted to pack solid detergent is integrally formed at its upper portion with a tear tape portion so as to open a lid part easily. Since the tear tape portion is formed at upper portions of vertical wall members of the paper box by a perforated line, outer air and humidity is easily penetrated through the perforated line, thereby causing the solid detergent packed in the box to be agglomerated easily.
Accordingly, the paper box is provided at its inner surface with an inlet such that the inlet covers the tear tape portion in order to improve its durability and prevent penetration of air.
Prevalent methods for providing the inlet include: method of inserting only the inlet, pouring detergent into a paper box and attaching tightly the inlet to a box surface by weight of the detergent contained the box, a method of fixing the inserted inlet to a box surface by rivetting, a method of supplying a cardboard blank adapted to form a box body and an inlet in the same direction to form a sheet of cardboard integrated with the inlet and shaping the integrated cardboard into a box, or a method of preparing a cardboard having four main walls 11, 12, 13 and 14 and three subsidiary walls 15, 16 and 17 and folding the subsidiary walls 15, 16 and 17 inward to define an inlet 20, as shown in FIG. 1.
However, since the inlet 20 formed by the last method is overlapped in its whole surface with an inner surface of a box body 10, the box is unnecessarily increased in its weight and an additional procedure for fixing the inlet 20 is required, thereby lowering productivity.
As shown in FIG. 2, the box body 10 may be also provided at a predetermined position with a hand strap 21 for facilitating its handling during distribution. The above hand strap is usually attached to upper portions of side walls of the box body 10. Both ends of the hand strap 21 are attached to the side walls by means of rivets 25. However, since the detergent contained the box may be early agglomerated by contact with outer air penetrated through rivet holes, the detergent is usually contained in a vinyl envelope and packed in the box 10. Hence, the vinyl envelope is frequently damaged by the protruded rivet portions and thus it is actually difficult to expect high reliance for detergent preservation.
In addition, since the hand strap 21 attached to the box 10, the rivets 25 and the vinyl envelope containing the detergent are made of material bringing about environmental pollution, many people's deep concern are concentrated upon the environmental pollution. Hence, as the protection of environment is emphasized, frequency in use of the material is gradually decreased.